Black & White Wrapping Paper What Kind Of Light Or Lamp Should I Use For A Science Fair Experiment On Heat Absorption?

What kind of light or lamp should I use for a science fair experiment on heat absorption? - black & white wrapping paper

The experiment used containers filled with water, each equipped with a thermometer. The pots are wrapped in paper ... white, gray and black. The temperature is measured over time. Appears to be a "sun causes" on the list of materials, but I'm not sure if this is better for the change of the angle (where the constant) and where you get to.

Thoughts and ideas about the things that I observe?